1. Field of the Invention
The present general inventive concept relates to an apparatus and method of compensating for defective nozzles, and more particularly, to an apparatus and method of compensating for image quality deterioration due to defective inkjet nozzles (i.e., nozzles that cannot discharge ink) of an image forming apparatus, such as an inkjet printer, by replacing data after moving a printer head to an optimum transfer position.
2. Description of the Related Art
An image forming apparatus such as an inkjet printer includes a plurality of inkjet nozzles. When some of the inkjet nozzles are defective, image quality may deteriorate. Examples of the defective nozzles include a nozzle that does not discharge ink and a nozzle that discharges an excessive amount of ink.
In order to compensate for image quality deterioration caused by defective nozzles, various methods have been proposed, such as a method of rearranging half-toned data and a method in which a dot to be formed by a defective nozzle is formed by a normal nozzle, after a printer head moves horizontally and places the normal nozzle in a position of the corresponding defective nozzle.
However, the hardware for implementing the former method in the case of a defective nozzle is very complicated due to a complex algorithm for rearranging the data, and a printed image may become distorted due to a rearrangement of a large amount of half-tone data. In particular, when a text portion or a graph portion which must not be rearranged is moved to another dot position by data rearrangement, the distortion of the printed image becomes very severe.
In addition, in the latter method, in which the printer head has to move many times to compensate for all the defective nozzles, a printing operation is performed several times per each line to be printed, which leads to a slow printing speed.